A vehicle may include assemblies for controlling activation or deactivation of a device. The automotive industry has required that such devices provide tactile feedback to a user to indicate when a function has been activated or deactivated. Tactile feedback may be achieved using associated mechanical components, such as a spring and lever in an “over the center” snap-acting arrangement (e.g. in a rocker mechanism), or by the use of other known tactile feedback configurations.
These configurations typically require several components and features. Some of the components may be difficult and expensive to manufacture. For example, a pivot race and pivot shaft for a rocker button may have narrow tolerances and require a highly polished surface to reduce frictional forces. Conventional assemblies may thus involve complex design, high costs, and reduced reliability. In addition, consumer preferences are leading automobile manufacturers to more streamlined and unobtrusive systems.
At least in part to address these issues, touch sensor configurations have been adopted. As used herein the term “touch sensor” refers to a sensor configuration that provides an output in response to contact with a touch area without requiring movement of a mechanical component to electrically close or open associated contacts. Numerous analog and digital touch sensor configurations are well-known to those of ordinary skill in the art. Known touch sensors use techniques such as resistive sensing, capacitive sensing, acoustic sensing, magnetic sensing, optical sensing, etc., to providing an output in response to contact with a touch area.
Touch sensor configurations may be less expensive compared to conventional mechanical switch devices, may require less space for installation, and may be more aesthetically pleasing. Typically, however, touch sensor configurations have not provided tactile feedback. Also, in multiple sensor configurations cross-talk between adjacent touch sensors may prevent or delay proper system operation, and conventional touch sensor systems may be challenged by harsh environmental conditions, e.g. rain, ice, extreme temperature, vibration, etc.
In many applications, due to space limitations, a limited number of touch sensors may be accommodated. In such applications, it may be desirable to use one or more touch sensors for more than one function. In other words, a plurality of touch sensors may be configured to each provide an output when individually touched and to provide a different output when touched substantially in parallel. For example, in automotive applications, unlocking a door may include a plurality of individual touch sensor touches in a specified sequence. Locking a door may include touching a plurality of touch sensors substantially in parallel, i.e., touching a first touch sensor and touching a second touch sensor while continuing to touch the first touch sensor. It may then be desirable to configure a touch sensor system to accommodate multiple functions for the touch sensors.
In some applications, e.g., an automotive door unlock sequence, a user may touch a known unlock sequence relatively rapidly. It may be desirable to detect the sequence of relatively rapid touches, store a portion or all of the sequence and output the sequence at a rate appropriate for a receiving device. It may also be desirable to differentiate between a user intentionally and unintentionally touching multiple touch sensors substantially in parallel in order to provide an appropriate response. For example, it may be desirable to not lock a vehicle doors in response to a user unintentionally touching multiple touch sensors, e.g., during car washing.
Although the following Detailed Description will proceed with reference being made to illustrative embodiments, many alternatives, modifications, and variations thereof will be apparent to those skilled in the art. Accordingly, it is intended that the claimed subject matter be viewed broadly.